Most elementary school teachers have not yet recognized the need for a single device for educational activities to demonstrate the complexities of ecosystem functioning, such as how plants and animals grow and live with each other, and how they interact with parts of the environment. Yet, legislation now requires that teachers teach concepts about total ecosystem functioning, not merely how plants and animals grow individually.
Heretofore, teachers and others have had no devices to demonstrate adequately these ecosystem complexities under approximately natural conditions. Instead, they have been compelled to "make do" with small containers such as glass aquariums, plastic milk or soda bottles, cups, saucers, or cages to grow plants and animals.
Small separate containers do not function for long-term observations and measurements (data collection) of natural phenomena for classroom environmental science education activities. Such containers may sometimes be suitable for observing the growth of a pea plant, or to watch a few guppies have babies, or to watch a gerbil use an exercise wheel. However, such "make do" containers cannot be used to demonstrate meaningfully natural interactions among and between plants and animals, or interactions between them and parts of their environment.
Small containers are inadequate for science and environmental teaching activities for at least four reasons. First, they are not big enough. An environmental teaching device must have enough room for several specimens of several species, and include aquatic and terrestrial plants and animals, and flying animals such as insects.
Secondly, with separate containers there can be no assured species movement (interchange) between the containers. Natural ecosystems, on the other hand, have many types of species freely occupying and moving about in the same area.
Thirdly, separate containers have either dirt or water. However, a science teaching device must have significant water and land zones large enough to support aquatic and terrestrial plants and animals and amphibians. In addition, animals must be able to move freely between the aquatic and terrestrial zones, especially if they are amphibious.
Fourthly, the individual containers used by teachers are not designed to include flying animals such as dragonflies, butterflies and other insects which are integral parts of the natural environment and should be integral parts of science education activities. An enclosure is needed that has enough room for small flying animals to actually fly about and choose to land in aquatic or terrestrial areas.
Containers which have air-impermeable sides and bottoms such as traditional glass or plastic aquariums and terrariums, cannot be used to demonstrate natural ecosystem functioning. These containers do not allow free air movement and heat exchange. The interiors become too hot for normal plant and animal functioning, and often too hot for life. What is needed is an enclosure whose sides allow for free air movement and heat exchange.
Glass-bottom containers also cannot be properly drained or set up for soil-saturation or evaporation/transpiration activities. That is because glass-bottom containers such as aquariums and terrariums do not have a means for bottom draining. What is needed is an enclosure that has a means for bottom draining.
In addition, the interiors of glass-sided containers are accessible only from the tops, making them less efficient for teaching purposes, and making it difficult to reach the biological specimens at the bottom. What is needed are openable or removable access panels on the sides as well as the top. Side access panels make a habitat enclosure much easier to set up, maintain, manipulate and clean.
Glass-sided containers also present a safety problem, in that children leaning on the sides may break the glass and become injured. Therefore, children are often told to remain at arms length from the glass containers, thus defeating the educational and observational purposes of the containers. What is needed is an enclosure made of a material other than breakable glass.
Heretofore, aquariums have housed aquatic animals; terrariums and vivariums have housed terrestrial animals. Aquariums have provided sufficiently for certain aquatic plants and animals. Likewise, terrariums have provided sufficiently for certain terrestrial plants and animals. A limited number of designs have attempted to combine aquariums and terrariums. However, a search of the prior art demonstrates that no design provides for the free interaction of terrestrial, aquatic and aereal animals in conditions which approximate the natural environment. The majority of previous inventions which combine terrariums and aquariums have separated--not integrated--terrestrial and aquatic areas. None provide from the containment of aereal animals. Therefore, the free association among all types of animals is not possible within these designs. And these designs, in many cases, actively prevent the environment from changing, as natural environments change over time.
As for turtles and amphibians, which require aquatic and terrestrial living areas, devices have been designed such as special aquariums, U.S. Pat. Nos. 4,995,334, 3,786,781, 3,804,064 and 4,176,620. A floating shoreline has also been patented, U.S. Pat. No. 4,788,938. Each of the above may be said to provide sufficiently for turtles and amphibians in that the animals can actually remove themselves from the water. However, removing themselves from the water is only one essential activity of these animals. These devices do not enable the animals to act naturally once they get out of the water: for example, it would be difficult or impossible for a turtle to lay eggs in the artificial substrate or to climb into a potted plant to lay eggs, as they would have to do in U.S. Pat. No. 4,788,938, or to lay eggs in the biologically unsuitable totally saturated mud of U.S. Pat. No. 4,176,620. Another device, U.S. Pat. No. 4,754,571, which is disclosed to be an aquarium/terrarium/humidifier, might be used to provide for turtles and amphibians, except that the flat vertical wall separating the water and land does not have a sloping shelf so that animals could hoist themselves and crawl onto the land.
As for terrestrial plants, glass or plastic aquariums and terrariums of the prior art are inadequate for natural reproduction and growth. If soil is applied to the bottom and plants are planted in it, they eventually die. This is because the bottom cannot be drained after water is applied, so the soil and root zones become saturated, eventually drowning the plants, or giving rise to allelopathic algae, fungus and bacteria which kill the plants. Alternatively, if the plants are placed in pots inside the terrarium, then the plants cannot vegetatively reproduce and spread. Also their roots become constricted, stunting plant growth.
As for aquatic plants, devices of the prior art do not provide for various growth depths required of different submersed and emersed aquatic plants. Different species require different water levels for reproduction and growth. Aquariums of the prior art contain only submersed plants, which represent only a small percentage of aquatic plants.
As for terrestrial animals, devices of the prior art do not give them a constant source of drinking water which cannot spill or which do not require frequent re-filling, nor does the prior art include pools large enough to accomodate terrestrial animals that swim, nor does the prior art provide water areas for prey-predator relationships wherein terrestrial animals hunt for prey along side and in pools of water.
As for flying animals such as large flying insects, no prior art provides for all life stages. Life stages for different flying insect species cannot be accomodated in previous aquariums or terrariums or combinations thereof. Life stages for various species require dirt, terrestrial plants, water, aquatic plants, and of course air to fly in. As one example, dragonflies have several growth stages, from eggs to aquatic larvae to pupae to adult flyers. A device to accomodate them would require a pool of water for egg-laying and growth of larvae and pupae, emersed plants for pupae attachment and metamorphosis, and of course a suitable volume of air for adult flying and for their prey. Other species such as ant lions have aquatic larvae, terrestrial pupae and aerial adults. A device for them would require water, land and air.
As for natural interaction among many species of different ecological zones (air, land, water), the prior art makes inadequate provision. The prior art provides for certain life stages of certain plants and animals, but none provides an environment for all life stages of small aquatic, terrestrial, amphibious and aerial plants and animals. It also would be very difficult to demonstrate natural interactions such as cross-pollination by flying insects in the cramped confines of the devices of the prior art.
In the field of the prior art, no invention overcomes the above described short-comings.